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%I #7 Nov 08 2022 11:07:48
%S 1,12,648,419904,3061100160
%N 1/2 number of n X n 0..8 matrices with MM' mod 9 = I.
%F Conjecture: a(n) = 3^(n*(n-1)/2) * A071302(n) for n >= 1. - _Michel Marcus_, Nov 08 2022
%Y Cf. A071302.
%K nonn,more
%O 1,2
%A _R. H. Hardin_, Jun 11 2002